1. Field of the Invention
The invention relates to a rotary motion transmission system for a stationary exercising bicycle. More specifically, the invention relates to such a transmission system for a stationary exercising bicycle which includes pedals and a fly wheel, the rotary motion of the pedals being transmitted to the fly wheel by the rotary motion transmission system which comprises a planetary gear arrangement.
2. Description of Prior Art
Stationary bicycles are known in the art as is illustrated in, for example, U.S. Pat. No. 4,452,445, Csekes, June 5, 1984, U.S. Pat. No. 3,964,742, Carnielli, June 22, 1976, U.S. Pat. No. 4,533,136, Smith et al, Aug. 6, 1985, U.S. Pat. No. 4,705,493, Lin, Nov. 10, 1987, U.S. Pat. No. 4,809,970, Beistegui, Mar. 7, 1989, U.S. Pat. No. 4,632,386, Beech, Dec. 30, 1986 and U.S. Pat. No. 4,789,153, Brown, Dec. 6, 1988.
In the Csekes patent, and referring to FIG. 1 thereof, the drum wheel 21 is equivalent to the ring gear of a planetary gear assembly. The drum wheel is connected, via free wheel 20 to shaft 5 which is connected to pedals 8 and 9. Thus, the drum wheel 21 will rotate with the rotation of the pedals. Rotation of the drum wheel causes rotation of pinion or planet gears 22, 23 and 24 (see also FIG. 2) about their own axis. Because of the engagement of the planet gears with the inner shaft 10 to the portion 26, rotation of the planet gears will cause the inner shaft 10 to rotate. Inner shaft 10 is connected to fly wheel 15. Thus, rotation of the pedals will cause rotation of the fly wheel 15.
In the Csekes arrangement, the fly wheel is coaxial with the pedal shaft and sits below the body of the exerciser and between his legs. Accordingly, unless he makes a special effort to do so, the exerciser cannot see the rotation of the fly wheel.
It has been found that exercisers prefer to see the motion of the fly wheel as this is an indication of their efforts.
The Carnielli patent also uses a planetary gear assembly which is illustrated in FIG. 5 of the patent and includes a central gear 58. Although there is very little description of how the planetary gear operates in the Carnielli patent, from FIGS. 1 and 3 it would appear that the shaft of the pedals is connected to the shaft of the central gear 58. Thus, rotation of the pedals would cause rotation of the carrier which is presumably connected to the fly wheel 62 of FIG. 3. Once again, in the Carnielli patent, the fly wheel is coaxial with the shaft of the pedals and sits under the exerciser between his legs. Thus, it suffers the same defects as the Csekes arrangement.
Smith et al teaches an arrangement wherein the pedals rotate about a horizontal axis whereas the fly wheel 84 rotates about a vertical axis. The patent also teaches an arrangement for transmitting the rotation of the pedals to the fly wheel.
In Lin, the transmission of the rotary motion from the pedals to the fly wheel is effected without any gears. Instead, there are a plurality of drive wheels and connecting chains which effect the transmission.
Beistegui teaches an arrangement wherein the shaft 2 of the pedals 15 is connected directly to the fly wheel 1 so that the fly wheel rotates directly with the rotation of the pedals. Rotation of the fly wheel causes rotation of the gear 5 which in turn causes rotation of gear 13. The purpose of the extra gears is to provide extra drag so that the fly wheel appears heavier than it actually is. In this patent, the fly wheel is, once again, beneath the exerciser and between his legs.
Beech also teaches an arrangement using a planetary gear for transmitting the rotation of the pedals to rotation of a fly wheel. In Beech, as in Carnielli, the shaft of the pedals is connected to the central gear. Also, in Beech, the fly wheel is beneath the exerciser and between his legs so it would not be immediately visible to an exerciser even if the casing 16 did not exist.
Brown teaches an arrangement wherein the fly wheel is not coaxial with the axis of the pedals. However, Brown teaches a rather complex transmission arrangement, illustrated in FIG. 15, and including an extra toothed wheel 636.